Method of purifying block copolymers

Abstract

The invention relates to block polymers, for example, arborescent copolymer compounds, and to methods of making and purifying such compounds. In one embodiment, the invention relates to arborescent polymer compounds that contain one or more styrene polymeric blocks in combination with one or more isobutylene polymeric blocks. In another embodiment, the invention relates to methods for purifying arborescent polymer compounds that contain at least one styrene polymeric block in combination with at least one isobutylene polymeric block.

1 . A method for purifying an arborescent block co-polymer comprising:
 dissolving the arborescent block co-polymer in one or more first solvents to form a first solution wherein the one or more first solvents dissolve the arborescent block co-polymer;   combining the first solution with one or more second solvents to produce a precipitated arborescent block co-polymer in a mother liquor wherein at least one of the one or more second solvents is selected from the group consisting of acetone, methyl ethyl ketone, and methyl vinyl ketone; and   separating the precipitated-arborescent block co-polymer from the mother liquor.   
     
     
         2 . The method of  claim 1 , further comprising:
 adding to the precipitated arborescent block co-polymer one or more solvents selected from the group consisting of acetone, methyl ethyl ketone, and methyl vinyl ketone to form a first mixture of precipitated arborescent block co-polymer and the one or more solvents;   combining the first mixture with one or more third solvents selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, tert-butanol and 1-butanol to form a second mixture of the precipitated arborescent block co-polymer and a mixture of solvents; and   separating the precipitated arborescent block co-polymer from the mixture of solvents to form a purified arborescent block co-polymer.   
     
     
         3 . The method of  claim 2 , wherein the one or more third solvent is methanol. 
     
     
         4 . The method of  claim 2 , wherein the purified arborescent block co-polymer comprises 5 ppm or more residual monomer. 
     
     
         5 . The method of  claim 2 , wherein the purified arborescent block co-polymer comprises less than 5 ppm residual monomer. 
     
     
         6 . The method of  claim 1 , wherein the one or more first solvents are selected from the group consisting of tetrahydrofuran and methylcyclohexane. 
     
     
         7 . The method of  claim 1 , wherein the one or more first solvents are selected from the group consisting of toluene and benzene. 
     
     
         8 . The method of  claim 1 , wherein the arborescent block co-polymer comprises an arborescent polyisoolefin block. 
     
     
         9 . The method of  claim 1 , wherein the arborescent block co-polymer comprises a homo or co-polymer vinyldiene arene block. 
     
     
         10 . The method of  claim 1 , wherein about 1 part by weight of the arborescent block co-polymer is dissolved in about 10 to 30 parts by weight of the one or more first solvents. 
     
     
         11 . The method of  claim 1 , wherein about 5 to about 10 volumes of the one or more second solvents based on a volume of the first solution is combined with the first solution. 
     
     
         12 . The method of  claim 1 , further comprising drying the purified arborescent block co-polymer. 
     
     
         13 . A method for purifying an arborescent block co-polymer comprising:
 dissolving the arborescent block co-polymer in one or more first solvents to form a first solution wherein the one or more first solvents dissolve the arborescent block co-polymer;   combining the first solution with one or more second solvents, to produce a precipitated arborescent block co-polymer in a mother liquor wherein at least one of the one or more second solvents is selected from the group consisting of acetone, methyl ethyl ketone, and methyl vinyl ketone;   separating the precipitated arborescent block co-polymer from the mother liquor;   adding to the precipitated arborescent block co-polymer one or more solvents selected from the group consisting of acetone, methyl ethyl ketone, and methyl vinyl ketone to form a first mixture of precipitated arborescent block co-polymer and the one or more solvents;   combining the first mixture with one or more third solvents selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, tert-butanol and 1-butanol to form a second mixture of the precipitated arborescent block co-polymer and a mixture of solvents; and   separating the precipitated arborescent block co-polymer from the mixture of solvents to form a purified arborcscent block co-polymer.   
     
     
         14 . The method of  claim 13 , wherein the arborescent block co-polymer comprises an arborescent polyisoolefin block. 
     
     
         15 . The method of  claim 13 , wherein the arborescent block co-polymer comprises a homo or co-polymer vinyldiene arene block. 
     
     
         16 . The method of  claim 13 , wherein the one or more first solvents are selected from the group consisting of tetrahydrofuran and methylcyclohexane. 
     
     
         17 . The method of  claim 13 , wherein the one or more first solvents are selected from the group consisting of toluene and benzene. 
     
     
         18 . The method of  claim 13 , wherein the one or more third solvent is methanol. 
     
     
         19 . The method of  claim 13 , wherein about 1 part by weight of the arborescent block co-polymer is dissolved in about 10 to 30 parts by weight of the one or more first solvents. 
     
     
         20 . The method of  claim 13 , wherein about 5 to about 10 volumes of the one or more second solvents based on a volume of the first solution is combined with the first solution. 
     
     
         21 . The method of  claim 13 , wherein the purified arborescent block co-polymer comprises 5 ppm or more residual monomer. 
     
     
         22 . The method of  claim 13 , wherein the purified arborescent block co-polymer comprises less than 5 ppm residual monomer. 
     
     
         23 . The method of  claim 13 , further comprising drying the purified arborescent block co-polymer. 
     
     
         24 . An arborescent block co-polymer purified by a method comprising:
 dissolving the arborescent block co-polymer in one or more first solvents to form a first solution wherein the one or more first solvents dissolve the arborescent block co-polymer;   combining the first solution with one or more second solvents to produce a precipitated arborescent block co-polymer in a mother liquor wherein at least one of the one or more second solvents is selected from the group consisting of acetone, methyl ethyl ketone, and methyl vinyl ketone;   separating the precipitated arborescent block co-polymer from the mother liquor;   adding to the precipitated arborescent block co-polymer one or more solvents selected from the group consisting of acetone, methyl ethyl ketone, and methyl vinyl ketone to form a first mixture of precipitated arborescent block co-polymer and the one or more solvents;   combining the first mixture with one or more third solvents selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, tert-butanol and 1-butanol to form a second mixture of the precipitated arborescent block co-polymer and a mixture of solvents; and   separating the precipitated arborescent block co-polymer from the mixture of solvents to form a purified arborescent block co-polymer.   
     
     
         25 . The arborescent block co-polymer of  claim 24 , wherein the purified arborescent block co-polymer contains 5 ppm or more residual monomer. 
     
     
         26 . The arborescent block co-polymer of  claim 24 , wherein the purified arborescent block co-polymer contains less than 5 ppm residual monomer. 
     
     
         27 . The arborescent block co-polymer of  claim 24 , wherein the arborescent block co-polymer comprises an arborescent polyisoolefin block. 
     
     
         28 . The arborescent block co-polymer of  claim 24 , wherein the arborescent block co-polymer comprises a homo or co-polymer vinyldiene arene block. 
     
     
         29 . The arborescent block co-polymer of  claim 24 , wherein the arborescent, block co-polymer exhibits properties of a plastic.